Conventional on-screen display (OSD) systems typically use a memory as a frame buffer for storing the actual display to be generated for a television screen or other display. The CPU generaters display information, for example a window, in a working memory space that is separate from the frame buffer memory. The CPU writes the window to a desired location in the frame buffer memory during a refresh or blanking period. Disadvantageously, such use of separate memory spaces can be expensive.
The present invention provides for real time calculation of window addresses in the CPU's working memory space. Such real time address calculation can, according to exemplary embodiments of the invention, advantageously eliminate the need for a separate frame buffer memory.